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Testing Status of Methapyrilene hydrochloride M20123


CASRN: 135-23-9

Formula: C14-H19-N3-S.Cl-H

Synonyms/Common Names

  • 1,2-Ethanediamine, N,N-dimethyl-N'-2-pyridinyl-N'-(2-thienylmethyl)-, monohydrochloride (9CI)

Short-Term Toxicity

  • 14-Day (Dosed-Feed)  (C55550D)  Completed 
    • Rats: F344/N; Mice: B6C3F1
  • 13-Week (Dosed-Feed)  (C55550D)  Completed 
    • Rats: F344/N; Mice: B6C3F1
    • Dose: R: 0, 100, OR 1200, M: 0, 500, OR 8000 PPM/24 PER GROUP.
  • 13 weeks (Dosed-Feed)  (C55550E)  Completed 
    • TOX-46 (NIH Number: 00-4407)  (Tox Peer Review 12/00/1999A )
      Hepatoxicity Studies of the Liver Carcinogen Methapyrilene Hydrochloride Administered in Feed to Male F344/N Rats
    • Rats: F344/N
    • Dose: MALE RATS: 0, 50, 100, 250, 1000 PPM; 40/GRP.

Long-Term Carcinogenicity

  • 6 weeks (Dosed-Feed)  (C55550A)  Completed 
    •   (Peer Review Approval 05/01/1979A ) Citation: W Lijinsky, MD Reuber, BN Blackwell, Liver Tumors Induced in Rats by Oral Administration of the Antihistaminic Methapyrilene Hydrochloride. Science 209:817-819 (1980)
    • Rats: F344/N; Mice: B6C3F1

Genetic Toxicology

  • In Vitro Cytogenetics (CA/SCE)  (184622)  Completed 
    • Sister Chromatid Exchange Positive 
    • Chromosome Aberrations Positive 
  • Mouse Lymphoma  (860299)  Completed 
    • Citation: McGregor, D., Brown, A., Howgate, S., McBride, D., Riach, C., and Caspary, W. Responses of the L5178Y tk+/tk- mouse lymphoma cell forward mutation assay. IV: 27 coded chemicals. Environ. Molec. Mutagen. Vol. 17 (1991) 196-219
    • Mice
    •  Negative 
  • Salmonella  (769480)  Completed 
    • Citation: Mortelmans, K., Haworth, S., Lawlor, T., Speck, W., Tainer, B., and Zeiger, E. Salmonella mutagenicity tests. II. Results from the testing of 270 chemicals Environ. Mutagen. Vol. 8 (Suppl 7) (1986) 1-119
    •  Negative